Saw grinder



Nav. 1, 1921.

w. E. KNoT'r SAW GRINDER Filed Nov.. 26,v `1925 3 Sheets-sheet 1 Nov. l, 1927.

W. E. KNOTT SAW GRINDER Filed Nov 26 1926 3 Sheets-Sheet 2 Nov. 1, 1927. 1,647,366 v W. E. KNOTT SAW GRINDER Filed Nov. 26, 1926 3 ASheets-Sheet 3 blanks out of shells or analogous objects.

Patented Nov.Y 1, 1927.

WARREN nxNo'rfr, or GRAND RAPIDS, MICHIGAN.

SAW GRINDER.

l `Application led November 26, 1926. Serial No, 150,729.. *i

This invention relates to saw grinders and particularly to an automatic grinder l.for sharpening, ,cylindical savvs. jf

The sawsfl to loe-sharpened by this device are of hollovvcylindrical or tubular shape,- the teeth being providedA at .one end ofthe cylinder and the cylinder lis .mounted inra mandrel adapted to be received by the chuck of the machine in which the saw is used. The sawsare particularly adapted for cutting disks out of material, such as button Theprincipal objects of the inventionare to provide a saw grinder vwhich will rapidly and` accurately automatically sharpen thel teeth of a saw of this character." The machine .is provided with means receiving the saw, means for accurately locating it -relative to means forv automatically acting upon saws i having different numbers of teeth, means for quicklyI changing the machine to` act i lhe mechanism embodying this invention 750i is designed to be applied to the saw grinding upon saws of' means for quickly inserting and removing the saw,` and various other novel features of construction and arrangement Vas are hereinafter more fully described and particularly pointed out in thenclaims, refer.-

ence being hadto the accompanying l ings, in which:

' Fig. 1 1s a partial'dfront elevation With parts broken away of'amach'ine en'iloodying this invention. z f

Fig. 2 'is a side .elevation of lthe-same. y Fig. 3 is a sectional-planen the line 3-3 ofFig.1. Fig.. 4 is a sectional detall of the upper end of the chuck. l y

Fig. 5 is a fragmentary shifting device.

Fig. 6 is an enlarged fragmentary detail grinding Wheel in Operative detail of the pavvl ofthe saw and relation, andv e 'Fig'. 7 is an enlarged fragmentary plan of the saw guide and saw.

. Like reference characters refer to like parts in the different figures of the drawings." Y

l machine disclosed 'byPatent No. 1,401,696,

dated vDeed/27,1921, ,and `utilizes parts of said machine Without change. The `machine shown bysaidgpatent includes 1a fra-me 1 oni i the top of vvhichis' averticalguidevvgay-2 forl quicklyv the. grinding Wheel, y

different numbers of teeth,l

provided v vithf a vertically reciprocablehe'ad 3 ony which .is mounted a grlndingv'vheelshaft 4 carrying vthe grinding -Wheeli rotated byaa belt 6 passingover a'pulleyY 7. The head?) With the grinding' ,vvhee'liis .caused to reciprocate vertically' by jcnechanisniWithinV the yframel, not rsh'ovvn in the present drawings, the 'connection `vvith such Amechanism being bymeans of .the rod 8 vvvhichis con# necte'd `to the head 3 bythe lugQ.l The rod 8 ,is adjustable'to .raise or lower the head 3.

The'patented machine also has anioscilla'ting arm 10 projecting through thetop of the 1 machine and oscillating in synchronism`vvith' the'reciprocation Aof the head 3; The meche anism for oscillating the arm 10 is disclosed by the said patent but is not shown by the present .drawings as it kforms no part of the present invention; v

Thecylindrical .saw 1l has teeth 12 in one of its ends'and is mounted at its other end in a mandrel 13 which has a tapered head, 14. y The tapered surface of the head 14 is provided with an annular grooveL lwhich receives means in the chuckxof the sawing machine to retain it. Analogous means are provided yin the chuck '16. of this grinding machine, comprising ballsl'? thrust inwardly by springs 18, lthe balls 17 engaging the inwardly tapered bottom of the` groove 15 to hold the taperedfhead 14 snugly in the tapered recess in the end of the chuck 51,6( Av pin 19`eXtendslaterally from the tapered surface of the `head 14a-nd 'is receivedin slot 2O in the end. of the chuckl. This pin prevents rotation -of` the mandrel relative tothe chuck. z l f The chuck 16l is mounted onk the upperl end fo-f the shaft 21, the lower end ofavhich is `supported for universal movement upon a vball 22, rtheball beingV supported by an` adjust-ingscrew 23 threaded into abracket 24 which is fixed tov the front lside of --the speci-fied.v The vchuck 16 is-g'uid'ed to its ape v Vproximately correct operating lposition by the forkedarcuate member25', thecurve of this member having'itscenter atthe ball 22.

1t is to be noted that the forked member 25 only approximately guides the chuckand that the chuck ts loosely between the forked members. The saw is accurately located in its operating position bythe guide 2,6 which has a V-shaped opening in its forward edge. The guide 26 is located relatively .close to the periphery of the grinding wheel 5 and its Vshaped recess receives the saw` close to the teeth thereof. l/Vhen the saw is engaged and located by the guide 26 it is intended that the chuck is not'tobe engaged by the forked member25.` y

AThe chuck and saw are held in operative position by a pivoted varm 27 mounted von the forked member 25 and provided with a spring 28 to engage the cylindrical surface of the chuck. A latch, comprising` t-he latch bolt 29 and the handle' 30, is provided on the lever 27 and a detent 31 on the forked member 25 which hold the arm 27 in position to engage the spring 28 with the chuck and yieldably move the chuck so that the saw will be heldy snugly in the guide 26. An auxiliary spring 32 acting upon a plunger 33 aids in pressing` the spring 28 against the chuck.

The operation of the machine in grinding tl saw is automatic and in performing its operation the grinding wheel 5 is caused to raise'and lower intermittently, coming in contact with the saw teeth at its lower position and while the grinding wheel is in raised position it is necessary to rotate the saw the distance of one tooth.v The step-by-step rotation of the saw is accomplished by means of a pawl acting upon a ratchet wheel. The teeth in the ratchet wheel correspond in Vnumber with the teeth of the saw and inasmuch as this machine isadapted to operate upon saws having different numbers of teeth, two such ratchet wheels 34 and 35 `are vprovided. each having a different number of teeth.i The oscillating arm 10 is provided with a bracket 36 rigidly attached to it and this bracket overhangsthe side ofthe ma# chine and is provided at its lower end with a lever 37 pivoted in a horizontal plane at the approximate 'elevation of the ratchet wheels 34 and 35. A pawl 38 is pivoted in a vertical plane to the end of the lever 37 and a forked guide 39 embraces the pawl 38 near its free end and guides it in engagement with one of the ratchet wheels 34 and 35. The forked guide 39 is pivoted at 40 to the front side of the frame and has a latch 41 engageable with the frame to retain the guide in 'either of two positions to which it may be turned. In one of these positions the pawl is guided into engagement with the upper ratchet wheel 34 and in the other position with the lower ratchet wheel 35. As the arm 10 oscillates the pawl 38 is moved backward and forward guided in the forked end of the guide 39 into engagement with one or the other u .ratchet wheels. The pivoting of the pawl 38 and to the'lever V37 retains the pawl in engagement with the ratchet wheels.

Itis to be understood that each saw is permanently fixed to its mandrel and each saw is provided with its own mandrel, and although the saws may be of dierent diameters and have diiferent'numbers of teeth the heads ofthe mandrels areall uniform.

l The removal of a saw and mandrel from the chuck 16 is accomplished by releasing the latch bolt 29 from the detent 31 and swinging the arm 27 outward thus releasing the chuck 16 and permitting it to swing outward upon its ball support 22. vVVh-en the arm 27 is swung outward on its pivot it is stopped by engagement lwith a lug 43 on the forked member 25 where it extends across the open-v ing between the forks and limits the outward movement of the chuck. A flange 16a is provided at the lower end of the chuck 16 and this flange is engaged by leaf springs 44 located nnde'r the forked -member 25 which offer a frictional resistance to the movement of the chuck, always retaining the lower end of the shaft 21 in 'engagement with the pawl 22 and preventing a rapid outward falling movement of the chuck when released. This outward position of the chuck is illustrated by dotted lines in Fig. 2. When in this po-V sition the mandrel is removed from the chuck 16 by pulling it outward with sufficient force to overcome the resistance o-f the retaining balls 17 and a different mandrel and saw are inserted by simply pushing the tapered head of the mandrel into the chuck until it is firmly seated in the tapering openingr and the balls engagek its annular groove. Slight variations in the size of the tapered heads 14 of the mandrels have no detrimental effect engaging the inwardly inclined surface of the annular groove-15.

In the operation of the machine the mandrel` with its saw is inserte-d as described, into the chuck 16 when the chuck is in outward position, and thechuck is then moved to its operating position being roughly guidedyin this movement by the fork-ed member 25 sufficiently to 'cause the saw to enter the Vs-shaped opening in the saw guide 25 which accurately locates the saw relative to the grinding wheel. l/Vhen in this position the arm 27 is swung to engage the spring 28 with the chuck'16v and the latch bolt- 29 is engaged with the vdetent 31. Although all of the saws are `'approximately the same length repeated grinding will vary their length and this variation, if great, may be compensated for bypvertical vadjustment of the shaft' and chuck by the adjusting screw 23. Fine variations are made by adjusting the operating rod 8 which raises or lowers llO naamw y the lpositionmof A the grincilii'ig Wheel?. The

"depth of cut is preferably regulatedby this inf latter `meansS-NVhen thersaw is in position to be ground the machine is started and theL engages`v the saw teeth at-the bolttomoffeach yvertical reciprocation, the periphery of the grinding wheel -being properly 4shaped to cut the-saw teethr at the prescribed angle. The arm.10\is,oscillated-so that it moves forward toward the grinding wheelv when ing in number. with the .teeth of lthe sawin the chuck. vAfter the in achine has been properly adjusted .and set-fin operation it automatically continues to grind all of the teeth of the saw one by one as thegrinding wheel is reciprocated and the chuck rotated. If the machine is leftto continueits operation after the saw has completed one rotation no further grinding will occur as tlie grinding wheel will merely come down to tlieposit-ionv relative to each tooth where it formerly came during the grinding operar` tion. Y*

The machine may be operated in another manner than that aboveV described by per mitting it to continue `to run while one saw and mandrel is beingremove'd and .a vnew one inserted.' .lVhen this mode of operation is carried out thehead 3 is elevated byineans of the adjustmentin the operating rod 8 at the end of one opera-tiontoraise the` grind-v ingwheel away from thesaw and the chuck isthen swungVV outward and anotherv saw [and mandrel placed `in itv and movedbackto operating position and thevgrinding' wheel lowered by said adjustment, while` itis'runf` ning, yinto engagement with the saw.

Theparticular object in locatingthe axi of the chuck and saw forward of. the axis of -the grinding wheel is to'permit the grinding wheel to engage the teeth on onel sidev ofthe sawonly, the curve ofthe periphery'ofthe grinding wheel vbringing itl free fromV the other side ofthe saw.. Another vadvantage -of this feature of the machine .is'thatg the saw teeth are grou-nd with a ilonger point on v ery of .the disk. before its Youteredge com# pletely passes through-the blank piece. This; insures a' smooth 'completely cut vvedge on the disk where otherwisejthe disk might vbe cut free from, ther .blank piece leaving `splinters ciently on' its vedge whichfliad not beenk fully ciitjoiffv by the saw teeth. Y a, One-ofthe chief; advantages of this inventioniis4 the-accurate location of the. saw relative to `rthev grinding wheel. :This is accomplished by means` ofV the-saw guirdeff26 closely adjacent .the periphery of the grinding wheel. and guiding the saw very close to' its teeth, .i By this' means inaccuracy .lof alignment of the saw .withthe mandrelfor .ofthe mandrel with the chuck have n0 per `c ept-ibleeifectnpon the relation ofthe saw with .thegrinding'wheel.` If suchinis-alignnient-is ,presentthe saw willzbe guided vaccurately relative to the grindingwheel',but theJJ chuck willgmove,eccentricallysuch eccentric. movement. being permitted .by y the clearance betweenthechuck and the forkedV member, vthe universal mounting yof the low er end lof the shaft 2land `the yielding action of the springffZS'. A Vfurther advantage l of this ftype off saw guide is thaty it will `receive'and7 accurately guide-.anyof the different diameters ofsaws Vwhich are/to ybe ground,-it-being understood` that the range of .diameters is limited.` Of course, a smaller diameter saw` will not come in yexactly the saine position underthe grinding Wheel .that

aplajrger l diameter sawwill but there is no cated ,relativeto thegrinding wheel sufli tioin .l Iclaiin: LAsawA grinding, machine Vincluding on itslongitudinal axis and a' V-pshap-ed guide engaged by the saw;V y. I n2. A saw grinding machine comprising a grinding element, means for holdinga cylin-- drical sanT to xturn on its longitudinal axis,

close tothe properoperating posi-v j meansfor holding a cylindrical saw to turn nov and a V-shaped guide closely adjacent; the

grindingelement and engaged; by the saw.

A saw grinding machine comprising a grinding Vwheel' and means for holding a .cylindrical saw. to turn on al longitudinal axi's,'" s'aid axis being oifset relative' to the axis `of thegrinding wheel'. e

4.: A` .saw grinding machine comprising a grinding wheel, means for holding a cylinf dricaljsaw to 4turn on a longitudinal axis, y

drical saw for rotation on -alongitudinal axis, and a guide engaged bythe sawclosey to the 'periphery ofthe grinding wheeljto hold the laxis of the saW offset from the axis of the grinding Wheel.

6. A saw grinding machine comprising a grinding Wheel, means for holding a cylinthe periphery of the grinding Wheel to, hold the saw with its axis odset from the axis ot' the grinding Wheel. y

8. A saw grinding machine comprising a reciprocable grinding Wheel, means for holding a cylindrical saw to turn upon its longitudinal axis, and means synchronized With the reciprocation or' the grinding Wheel for rotating the saw step by step.

9. A saw grinding machine comprising a reciprocable grinding machine, means for holding acylindrical saw to turn upon its longitudinalv axis, `means engageable With the cylindrical surface oi;I the saW to rguide the saw relative to the grinding Wheel, and means synchronized With the reciprocation of the grinding wheel for rotating the saw step by step.

10. A saw grinding machine comprising a. reciprocable grinding Wheel, means for holding a cylindrical saw to turn upon its longitudinal axis, guide means closely adjacent the periphery ofthe grinding Wheel and engageable With the cylindrical surface -otthe saw, and means synchronized With the reciprocation of the grinding Wheel for rotating the saw step by step.

11. A saw grinding machine comprising a reciprocable grinding Wheel, means forI holding a cylindrical saw to turn upon its longitudinal axis, a V-shaped guide to locate t-he saw relative to the grinding Wheel, and means synchronized with the reciprocation of the grinding Wheel to rotate the saW step by step.

12. 'A saw grinding machine comprising a reciprocable grinding Wheel, means for holding a cylindrical saw to turn upon its longitudinal axis, a V-shaped guide engageable with the savv close` to the `grinding Wheel, and means synchronized With the reciprocation of the grinding Wheel to rotate the saw step by step.

13. A saw grinding machine comprising a grinding Wheel, means for holding a cylindrical saw, said means being mounted for universal movement, and a guide closely adljacent the grinding Wheel and engageable with said saw.

14. A saiv grinding machine comprising a grinding Wheel, means for holding a cylindrical saw, said means being mounted for universal movement, and a V-shaped guide' means for holding a cylindrical saw for ro tation on its longitudinal axis, a ratchet Wheel on said holding means, and means including a paWl engageable With said ratchet wheel for imparting a step-by-step rotary movement to said holding means and saw.

18. A saw grinding machine including means for holding a cylindrical saW for rotation on its longitudinal axis, a plurality of ratchet Wheels on said holding means, means including a paWl engageable With either oil said ratchet Wheels for imparting a step-by-step rotary motion to said `holding means, and means tor guidingsaid pawl toA engagement With either of said ratchet Wheels.

19. A saw grinding machine including means for holding a cylindrical savv for rotation on its longitudinal axis, a plurality oi:v ratchet Wheels onv said holding means, a reciprocably mountedv pavvl, and a mov able guide operatively connected With said pavvl to guide the paWl into engagement with either of said ratchet Wheels.v

20. A saw grinding machine comprising a grinding Wheel, means for holding` a cylindrical saw for rotation on its longitudinal axis, and means for axially adjusting said holding means whereby the saw teeth are adjusted relative tothe grinding Wheel.

21. A saw grinding machine comprising a grinding Wheel, means for holding a cylindrical saw for rotation on its longitudinal axis, said means also mounted for lateral movement, and releasable means for retaingrinding wheel.

22. A saw grinding machine including a chuck adapted to receive a cylindrical saw mandrel, said Lchuck being mounted for axial rotation and lateral movement, and means for releasably holding said chuck in saW grinding position.

23. A saw grinding machine including a chuck adapted to releasably receive a cylindrical saw mandrel, said chuck being mounted for axial rotation and lateral movement, a saw guide, and releasable means to hold a saw mounted in said chuck and in engagement with said sawv guide.

24. A saw grinding machine including a lng the saw in operative relation to the chuck adapted to releasably receive a cylin-Iy drical saw mandrel, said chuck being mounta grinding Wheel, a chuck adapted to releasably receive a cylindrical saw mandrel, said chuck being mounted for vaxial rotation and for lateral movement, a saw guide closely adjacent the grinding Wheel, and means for holding tlie saw inengagement with the saWl guide. v Y

26. A saw grinding machine comprising a grinding Wheel, a chuck adapted to releasably receive a cylindrical saw mandrel, said chuck being mounted for -axial rotation and for lateral movement, and means associated with the chuck for holding the saw in engagement with the saw guide.

,-27. A saw grinding machine includinga chuck to releasably receive a cylindrical saw mandrel, a bearing to support said chuck f for vrotating and universal swinging movement', and means for axially adjusting said supporting hearingz ,l 28. A saW grinding `machine comprising an grinding wheel, ,a chuck to releasaloly ie--' ceive a cylindrical saw mandrel, a universal support for said chuck, a guidato permit: lswinging movement oiA said chuck, a saW guide closely adJacentsaid grinding Wheel,

and yieldaloley and re-leasableineans associated With said chuck to lhold the saw in engagement with said saw guide.

, In testimony whereof I ailix my signature.

` WARREN KNOTT. 

